Sync countries when triggered

Author: Ecarrion

WooCommerce/Classes/ViewRelated/Orders/Order Details/Address Edit/EditAddressFormViewModel.swift

@@ -33,6 +33,7 @@ final class EditAddressFormViewModel: ObservableObject {
         self.storageManager = storageManager
         self.stores = stores
         updateFieldsWithOriginalAddress()
+        bindSyncTrigger()
         fetchStoredCountriesAndTriggerSyncIfNeeded()
     }
 
@@ -57,6 +58,10 @@ final class EditAddressFormViewModel: ObservableObject {
 
     // MARK: Navigation and utility
 
+    /// Define if the view should show placeholders instead of the real elements.
+    ///
+    @Published private(set) var showPlaceholders: Bool = false
+
     /// Return `true` if the done button should be enabled.
     ///
     var isDoneButtonEnabled: Bool {
@@ -112,4 +117,37 @@ private extension EditAddressFormViewModel {
             return syncCountriesTrigger.send()
         }
     }
+
+    /// Sync countries when requested. Defines the `showPlaceholderState` value depending if countries are being synced or not.
+    ///
+    func bindSyncTrigger() {
+        syncCountriesTrigger
+            .handleEvents(receiveOutput: { // Set `showPlaceholders` to `true` before initiating sync.
+                self.showPlaceholders = true // I could not find a way to assign this using combine operators. :-(
+            })
+            .map { // Sync countries
+                self.makeSyncCountriesFuture()
+                    .replaceError(with: ()) // TODO: Handle errors
+            }
+            .switchToLatest()
+            .map { _ in // Set `showPlaceholders` to `false` after sync is done.
+                false
+            }
+            .assign(to: &$showPlaceholders)
+    }
+
+    /// Creates a publisher that syncs countries into our storage layer.
+    ///
+    func makeSyncCountriesFuture() -> AnyPublisher<Void, Error> {
+        Future<Void, Error> { [weak self] promise in
+            guard let self = self else { return }
+
+            let action = DataAction.synchronizeCountries(siteID: self.siteID) { result in
+                let newResult = result.map { _ in } // Hides the result success type because we don't need it.
+                promise(newResult)
+            }
+            self.stores.dispatch(action)
+        }
+        .eraseToAnyPublisher()
+    }
 }